U.S. patent application number 11/306238 was filed with the patent office on 2007-07-12 for methods for ligament reconstruction.
Invention is credited to Gregory R. Whittaker.
Application Number | 20070162122 11/306238 |
Document ID | / |
Family ID | 38233719 |
Filed Date | 2007-07-12 |
United States Patent
Application |
20070162122 |
Kind Code |
A1 |
Whittaker; Gregory R. |
July 12, 2007 |
METHODS FOR LIGAMENT RECONSTRUCTION
Abstract
Methods and devices are provided for fixing a ligament graft in
a bone tunnel. In general, the methods and devices involve affixing
a ligament graft within a bone tunnel using an adhesive. A fixation
device can be inserted through the ligament graft in a direction
transverse to an axis of the tunnel to maintain the ligament graft
in contact with the adhesive. The fixation device can be removed
when the adhesive is cured such that the ligament graft is fixed in
the tunnel.
Inventors: |
Whittaker; Gregory R.;
(Stoneham, MA) |
Correspondence
Address: |
NUTTER MCCLENNEN & FISH LLP
WORLD TRADE CENTER WEST
155 SEAPORT BOULEVARD
BOSTON
MA
02210-2604
US
|
Family ID: |
38233719 |
Appl. No.: |
11/306238 |
Filed: |
December 20, 2005 |
Current U.S.
Class: |
623/13.14 |
Current CPC
Class: |
A61F 2002/0882 20130101;
A61F 2002/087 20130101; A61F 2002/0829 20130101; A61F 2/0811
20130101; A61F 2002/0852 20130101 |
Class at
Publication: |
623/013.14 |
International
Class: |
A61F 2/08 20060101
A61F002/08 |
Claims
1. A method for fixing a ligament graft in a bone tunnel,
comprising: inserting a ligament graft at least partially into a
first bone tunnel formed in a femur or tibia; introducing an
adhesive into the first bone tunnel; inserting a fixation device
through a transverse tunnel that intersects the first bone tunnel,
the fixation device maintaining a first end of the ligament graft
in the first bone tunnel in contact with the adhesive; tensioning
the ligament graft and fixing a second end of the ligament graft in
a second bone tunnel formed in the other one of the femur or tibia;
and removing the fixation device when the adhesive is cured.
2. The method of claim 1, wherein the first bone tunnel includes an
end wall formed therein.
3. The method of claim 2, wherein the transverse tunnel intersects
the first bone tunnel adjacent the end wall.
4. The method of claim 3, wherein the adhesive is introduced
through the transverse tunnel such that the adhesive is disposed
adjacent to the end wall of the first bone tunnel.
5. The method of claim 4, wherein the ligament graft is positioned
a distance apart from the end wall of the first bone tunnel prior
to introducing the adhesive, and wherein the ligament graft is
pulled toward the end wall and into contact with the adhesive after
the adhesive is introduced into the first bone tunnel.
6. The method of claim 1, wherein the ligament graft is pulled
through the first bone tunnel using a suture attached thereto.
7. The method of claim 6, wherein, prior to inserting a fixation
device, the suture is tensioned to pull the first end of the
ligament graft into the adhesive.
8. The method of claim 1, wherein the fixation device is inserted
through a loop formed on the ligament graft.
9. The method of claim 1, wherein the ligament graft includes an
anchor coupled to at least one of the first and second ends
thereof.
10. The method of claim 1, wherein an anchor is coupled to the
first end of the ligament graft, and wherein the fixation device is
inserted into the anchor to maintain the first end of the ligament
graft in the femoral tunnel.
11. The method of claim 1, wherein the fixation device includes a
protective coating disposed thereon and adapted to prevent adhesion
between the adhesive and the cross-pin.
12. The method of claim 11, wherein the protective coating is
formed from a fluoropolymer plastic resin.
13. The method of claim 1, wherein the adhesive is introduced
through a sleeve disposed at least partially through the first bone
tunnel.
14. The method of claim 1, wherein the adhesive is selected from
the group consisting of a bioabsorbable adhesive and a
non-absorbable adhesive.
15. The method of claim 1, wherein the fixation device comprises a
cross-pin.
16. A method for fixing a ligament graft in a bone tunnel,
comprising: inserting a ligament graft at least partially into a
first tunnel formed in bone; introducing an adhesive into the first
tunnel; inserting a fixation device to maintain the ligament graft
in contact with the adhesive; and removing the fixation device when
the adhesive is cured such that the ligament graft is fixed in the
tunnel.
17. The method of claim 16, further comprising, prior to removing
the fixation device, applying tension to a free end of the ligament
graft and securing the free end of the ligament graft in a second
tunnel formed in bone.
18. The method of claim 16, wherein the first tunnel includes an
end wall formed therein, the ligament graft being fixedly attached
to the end wall.
19. The method of claim 18, wherein the adhesive is introduced
through a separate tunnel and is disposed adjacent to the end
wall.
20. The method of claim 20, wherein the ligament graft is pulled
into contact with the adhesive after the adhesive is disposed
adjacent to the end wall of the first tunnel.
21. The method of claim 16, wherein the fixation device comprises a
cross-pin that is inserted through a loop formed on the ligament
graft.
22. The method of claim 16, wherein the adhesive is selected from
the group consisting of a bioabsorbable adhesive and a
non-absorbable adhesive.
23. The method of claim 16, wherein the fixation device includes a
protective coating disposed thereon and adapted to prevent adhesion
between the adhesive and the fixation device.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to methods and devices for
affixing ligament grafts in bone tunnels.
BACKGROUND OF THE INVENTION
[0002] Joint injuries may commonly result in the complete or
partial detachment of ligaments, tendons and soft tissues from
bone. Tissue detachment may occur in many ways, e.g., as the result
of an accident such as a fall, overexertion during a work-related
activity, during the course of an athletic event, or in any one of
many other situations and/or activities. These types of injuries
are generally the result of excess stress or extraordinary forces
being placed upon the tissues.
[0003] In the case of a partial detachment, commonly referred to
under the general term "sprain," the injury frequently heals
without medical intervention, the patient rests, and care is taken
not to expose the injury to undue strenuous activities during the
healing process. If, however, the ligament or tendon is completely
detached from its attachment site on an associated bone or bones,
or if it is severed as the result of a traumatic injury, surgical
intervention may be necessary to restore full function to the
injured joint. A number of conventional surgical procedures exist
for re-attaching such tendons and ligaments to bone.
[0004] One such procedure involves the re-attachment of the
detached tissue using "traditional" attachment devices such as
staples, sutures, and bone screws. Such traditional attachment
devices have also been used to attach tendon or ligament grafts
(often formed from autologous tissue harvested from elsewhere in
the body) to the desired bone or bones. In one procedure, a damaged
anterior cruciate ligament ("ACL") is replaced in a human knee.
Initially bone tunnels are formed through the tibia and femur at
the points of normal attachment of the anterior cruciate ligament.
Next, a ligament graft with a bone graft on one of its ends is
sized so as to fit within the bone tunnels. Suture is then attached
to the bone graft and thereafter passed through the tibia and
femoral bone tunnels. The bone graft is then pulled through the
tibial tunnel and up into the femoral tunnel using the suture. As
this is done, the ligament graft ligament extends back out of the
femoral tunnel, across the interior of the knee joint, and then
through the tibial tunnel. The free end of the ligament graft
ligament resides outside the tibia, at the anterior side of the
tibia. Next, a bone screw is inserted between the bone graft and
the wall of femoral bone tunnel so as to securely lock the bone
graft in position by a tight interference fit. Finally, the free
end of the ligament graft ligament is securely attached to the
tibia.
[0005] In another ACL reconstruction procedure, aligned femoral and
tibial tunnels are initially formed in a human knee. A bone graft
with a ligament graft attached thereto is passed through the
tunnels to a blind end of the femoral tunnel where the block is
fixed in place by an anchor. The ligament extends out of the tibial
tunnel, and the end is attached to the tibia cortex by staples or
the like. Alternatively, the end of the ligament may be fixed in
the tibial tunnel by an anchor or by an interference screw. Various
types of ligament and/or suture anchors for attaching soft tissue
to bone are also well known in the art. A number of these devices
are described in detail in U.S. Pat. Nos. 4,898,156, 4,899,743,
4,968,315, 5,356,413, and 5,372,599, all of which are commonly
assigned to Mitek Surgical Products, Inc., a Johnson &Johnson
company, and which are incorporated by reference in their
entirety.
[0006] One known method for anchoring bone grafts in bone tunnels
is through a "cross-pinning" technique, in which a pin, screw, or
rod is driven into the bone transversely to the bone tunnel so as
to intersect the bone graft and thereby cross-pin the bone graft in
the bone tunnel. In order to provide for proper cross-pinning of
the bone graft in the bone tunnel, a drill guide is generally used.
The drill guide serves to ensure that the transverse passage is
positioned in the bone so that it will intersect the appropriate
tunnel section and the bone graft.
[0007] While cross-pinning is effective, there is a continuing need
for improved methods and devices for fixing a ligament graft in a
bone tunnel.
BRIEF SUMMARY OF THE INVENTION
[0008] The present invention generally provides methods and devices
for fixing a ligament graft in a bone tunnel. In one exemplary
embodiment, the method can include drilling a first tunnel in bone
and inserting a ligament graft at least partially into the first
tunnel. An adhesive is introduced into the first tunnel, and a
fixation device is inserted through the ligament graft in a
direction substantially transverse to an axis of the tunnel to
maintain the ligament graft in contact with the adhesive. The
cross-pin can be removed when the adhesive is cured such that the
ligament graft is fixed in the first tunnel.
[0009] While the method can be used in a variety of surgical
procedures, in one exemplary embodiment the method is used to
repair an anterior cruciate ligament. Thus, the ligament graft can
be at least partially inserted into a femoral or tibial tunnel
formed in a femur or tibia, and the adhesive is introduced into the
femoral or tibial tunnel. A fixation device, such as a cross-pin,
can be inserted through a transverse tunnel formed in the femur or
tibia and intersecting the femoral or tibial tunnel. In certain
exemplary embodiments, the transverse tunnel can include a sleeve
disposed therein and defining a pathway to the femoral or tibial
tunnel. The fixation device is effective to maintain a first end of
the ligament graft in the femoral or tibial tunnel in contact with
the adhesive. A second end of the ligament graft can then be
tensioned and fixed in the other one of the femoral or tibial
tunnel, while the adhesive is drying. Once the adhesive is cured,
the fixation device can be removed.
[0010] The first tunnel can have a variety of configurations, and
it can extend only partially through the femur or tibial, or fully
through the femur or tibia. In one embodiment, the first tunnel
includes an end wall formed therein. The transverse tunnel can
intersect the first tunnel adjacent the end wall. The adhesive can
thus be introduced through the transverse tunnel such that the
adhesive is disposed adjacent to the end wall of the first tunnel.
In one exemplary embodiment, the ligament graft is positioned a
distance apart from the end wall of the first tunnel prior to
introducing the adhesive, and it is pulled toward the end wall and
into contact with the adhesive after the adhesive is introduced
into the first tunnel. The ligament graft can optionally be pulled
through the first tunnel using a suture attached thereto.
[0011] In other embodiments, the ligament graft can be directly
adhered to the first tunnel, or alternatively it can be coupled to
an anchor, such as a bone graft. Where an anchor is used, the
fixation device can be inserted through the anchor and the adhesive
can be disposed around and optionally within the anchor. In yet
another embodiment, the adhesive can be formed from a bioabsorbable
material, such that it is eventually absorbed by the body.
Alternatively, the adhesive can be a non-absorbable adhesive. In
yet another embodiment, the fixation device can be adapted to
prevent adhesion between the adhesive and the fixation device. For
example, the fixation device can include a protective coating
disposed thereon, or it can be formed from a protective material,
such as a fluoropolymer plastic resin. The sleeve disposed within
the transverse tunnel can also include a protecting coating, or it
can be formed from a protective material.
[0012] In other embodiments, a method for fixing a ligament graft
in a bone tunnel is provided and includes coupling an anchor to the
bone graft, introducing the anchor and bone graft into a bone
tunnel, and introducing an adhesive into the bone tunnel such that
the adhesive surrounds at least a portion of the anchor, thereby
affixing the anchor within the bone tunnel. The anchor can have a
variety of configurations, but in one embodiment it has a first
portion that is adhered to the bone tunnel, and a second portion
that mates to the bone graft. The first portion can include a post
with an eyelet formed on a terminal end thereof. In order to
introduce the anchor and bone graft into a bone tunnel, a suture
can be attached to the eyelet and tensioned the suture to pull the
bone graft into the bone tunnel. The second portion of the anchor
can also have a variety of configurations. For example, it can
include threads formed thereon for threading the second portion
into the bone graft. In another embodiment, the second portion can
be mated to the bone graft using sutures. In particular, the second
portion can include opposed arms, and the bone graft can be mated
to the opposed arms by passing at least one suture through the
opposed arms and through the bone graft.
[0013] In yet another embodiment, a ligament graft is provided and
includes a bone graft having a ligament extending therefrom, and an
anchor having a first portion mated to the bone graft, and a second
portion having at least one surface feature adapted to receive an
adhesive for adhesively mating the second portion to a bone tunnel.
The surface feature on the second portion of the anchor can be, for
example, an eyelet having an opening extending therethrough, at
least one cut-out portion, or other surface features.
[0014] In other aspects, a method for fixing a ligament graft in a
bone tunnel is provided and includes modifying the bone graft with
a ligament attached thereto to include at least one cut-out
portion, introducing the bone graft into a bone tunnel, and
introducing an adhesive into the bone tunnel such that the adhesive
surrounds at least a portion of the bone graft and extends into the
at least one cut-out portion, thereby affixing the bone graft
within the bone tunnel. The bone graft can be modified by, for
example, forming a plurality of grooves around or on the bone
graft, forming at least one thru-bore in the bone graft, etc.
[0015] In yet another embodiment, a method for fixing a ligament
graft in a bone tunnel is provided and includes coupling a soft
tissue ligament to an anchor, introducing the anchor into a bone
tunnel, and introducing an adhesive into the bone tunnel such that
the adhesive surrounds at least a portion of the anchor, thereby
affixing the anchor with the soft tissue ligament extending
therefrom within the bone tunnel. The anchor can include a first
portion having surface features formed thereon that receive the
adhesive therebetween to mate the first portion within the bone
tunnel, and a second portion having a mating element that mates to
a soft tissue graft. The mating element can be, for example, an
eyelet.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The invention will be more fully understood from the
following detailed description taken in conjunction with the
accompanying drawings, in which:
[0017] FIG. 1 illustrates a human knee and a guide device having a
cannulated guide rod extending through bone tunnels formed in the
tibia and femur;
[0018] FIG. 2 illustrates the human knee and guide device of FIG.
1, showing a sleeve and trocar assembly being inserted through the
femur to form a transverse tunnel that intersects the femoral
tunnel;
[0019] FIG. 3 illustrates the human knee of FIG. 2 with the guide
device and the trocar removed, leaving the sleeve extending into
the transverse tunnel, and a ligament graft extending through the
tibial tunnel and into the femoral tunnel;
[0020] FIG. 4 illustrates the human knee of FIG. 3, showing a
syringe inserted through the sleeve in the transverse tunnel and
injecting an adhesive into the femoral tunnel;
[0021] FIG. 5 illustrates the human knee of FIG. 4, showing the
ligament graft pulled further into the femoral tunnel and into
contact with the adhesive such that the adhesive surrounds an end
of the ligament graft;
[0022] FIG. 6 illustrates the human knee of FIG. 5, showing a
cross-pin being inserted through the sleeve, into the transverse
tunnel, and through the ligament graft to maintain the ligament
graft in a fixed position within the femoral tunnel;
[0023] FIG. 7 illustrates the human knee of FIG. 6 showing the
sleeve removed leaving the cross-pin in place;
[0024] FIG. 8 illustrates the human knee of FIG. 7 showing the
cross-pin removed after the adhesive has cured; and
[0025] FIG. 9A is a side perspective view of one exemplary
embodiment of an anchor configured to mate to a bone graft and to
be affixed within a bone tunnel;
[0026] FIG. 9B is a side perspective view of the anchor shown in
FIG. 9A mated to a bone graft with a ligament graft extending
therefrom;
[0027] FIG. 9C is an illustration showing the anchor, bone graft,
and ligament graft of FIG. 9B implanted within a bone tunnel in
bone, showing space in the bone tunnel for receiving an
adhesive;
[0028] FIG. 10 is a side perspective view of another embodiment of
an anchor configured to mate to a bone graft and to be affixed
within a bone tunnel to anchor the bone graft within the bone
tunnel, the anchor having annual grooves for receiving an
adhesive;
[0029] FIG. 11A is a side view of another embodiment of an anchor
and a bone graft, each having suture bores formed therein for
mating the bone graft to the anchor;
[0030] FIG. 11B is another side view of the anchor and bone graft
shown in FIG. 11A;
[0031] FIG. 11C is a side view of the anchor and bone graft shown
in FIGS. 11A and 11B mated to one another using sutures;
[0032] FIG. 12A is a perspective view of one exemplary embodiment
of a bone graft modified to have a cross-shaped cut-out for
receiving adhesive therein;
[0033] FIG. 12B is a perspective view of another exemplary
embodiment of a bone graft modified to have annular grooves for
receiving adhesive therein;
[0034] FIG. 12C is a perspective view of yet another exemplary
embodiment of a bone graft modified to have thru-bores features for
receiving adhesive therethrough;
[0035] FIG. 12D is a perspective view of another exemplary
embodiment of a bone graft modified to have a post formed thereon
for receiving adhesive therearound; and
[0036] FIG. 13 is a perspective view of yet another embodiment of
an anchor having surface features for receiving adhesive
therearound, and having a mating element for mating to a ligament
graft.
DETAILED DESCRIPTION OF THE INVENTION
[0037] The present invention provides methods and devices for
fixing a ligament graft in a bone tunnel. The various methods and
devices disclosed herein can be used in a variety of surgical
procedures, however the methods and devices are particularly useful
for repairing an anterior cruciate ligament (ACL) in a human knee.
In an ACL repair, the torn ACL is replaced with a ligament graft
which is anchored to the tibia and femur. The term "ligament
graft," as used herein, is intended to include natural materials,
such as autografts, allografts, and xenografts, including harvested
ligaments and tendons, as well as synthetic materials. The ligament
graft can also include an anchoring element attached thereto for
anchoring the graft to the tibia and femur. For example, the
ligament graft can include a bone graft, plug, or other member,
attached to one or both terminal ends thereof. The term "bone
graft," as used herein, in intended to include natural materials,
such as autografts, allografts, and xenografts, as well as
synthetic materials.
[0038] A person skilled in the art will appreciate that the various
methods and devices disclosed herein can be used in a variety of
surgical procedures, and that the particular configuration of the
ligament graft can vary depending on the intended use, and
virtually any ligament graft known in the art can be used with the
methods disclosed herein.
[0039] FIGS. 1-8 illustrate one exemplary method for anchoring a
ligament graft in a bone tunnel, and in particular in femoral and
tibial tunnels of a human knee. In general, the method includes
drilling a tunnel in bone and inserting a ligament graft at least
partially into the tunnel. An adhesive is introduced into the
tunnel, and a fixation device is inserted through the ligament
graft in a direction transverse to an axis of the tunnel to
maintain the ligament graft in contact with the adhesive. The
fixation device can be removed when the adhesive is cured such that
the ligament graft is fixed in the tunnel. The use of a fixation
device to maintain the ligament graft in the tunnel while the
adhesive cures allows an opposed end of the ligament graft to be
tensioned and fixed using the same or a different anchoring
technique. The method is described in connection with certain
exemplary procedures for preparing bone tunnels and inserting a
ligament graft into the bone tunnels. For example, in certain
exemplary methods, the ligament graft is affixed in the femoral
tunnel prior to affixing it in the tibial tunnel. However, a person
skilled in the art will appreciate that the ligament graft can be
affixed in the tibial tunnel first or at the same time. A person
skilled in the art will also appreciate that a variety of other
procedures known in the art can be used to prepare the bone tunnels
and to the insert a ligament graft into the bone tunnels.
[0040] Referring first to FIG. 1, a bone tunnel is drilled through
the tibia 50 and femur 60, using conventional surgical equipment
and techniques, to form a tibial tunnel 52 and femoral tunnel 62.
The tibial and femoral tunnels 52, 62 can extend completely through
the tibia and femur 50, 60, however in an exemplary embodiment the
femoral tunnel 62 terminates part way through the femur 60 such
that a femoral socket is formed. A suture tunnel 64 can optionally
extend through the remainder of the femur 60 in longitudinal
alignment with the femoral tunnel 62 to allow a suture to pass
therethrough and pull and graft into the tunnels 52, 62, as will be
discussed in more detail below. The suture tunnel 64 preferably has
an inner diameter that is less than an inner diameter of the
femoral tunnel, such that a terminal end of the femoral tunnel
defines an end wall 62e.
[0041] Once the tibial and femoral tunnels 52, 62 are prepared, a
transverse tunnel can be formed in the femur. The transverse tunnel
preferably intersects the femoral tunnel 62 such that a pathway is
formed through the transverse tunnel to the femoral tunnel 62. This
pathway can be used to inject an adhesive into the femoral tunnel
62, as will be discussed in more detail below. As shown in FIG. 1,
a guide device 10 can optionally be used to locate and align the
transverse tunnel. As shown, the guide device 10 generally includes
an L-shaped frame 12 having a cannulated guide rod 14 extending
from one end thereof, and a housing with an opening 16 formed
therethrough on an opposed end thereof. The cannulated guide rod 14
can be inserted through the tibial tunnel 52 and the femoral tunnel
62 to maintain the guide frame 12 in a fixed position. As shown in
FIG. 2, a sleeve and trocar assembly 70, 72 can then be inserted
through the opening 16 in the housing on the guide frame 12, and
drilled into the lateral side of the femur until the sleeve and
trocar abut the cannulated guide rod 14. The transverse tunnel 66
will thus extend through the femur and into the femoral tunnel 62,
preferably at a location substantially adjacent to the distal end
wall 62e of the femoral tunnel. A person skilled in the art will
appreciate that the transverse tunnel 66 can extend at any angle
relative to the femoral tunnel 62. After the transverse tunnel 66
is completely formed, the trocar 72 can be removed leaving the
sleeve 70 in place, as shown in FIG. 3. The sleeve 70 can be
inserted partially into the transverse tunnel 66, such that it does
not extend into the femoral tunnel 62, or alternatively the sleeve
70 can at least partially extend into the femoral tunnel 62. This
will allow the sleeve 70 to function as a stop for the ligament
graft, as will be discussed in more detail below. The procedure
can, however, be performed without the use of the sleeve 70.
[0042] After the tibial, femoral, and transverse tunnels 52, 62, 66
are formed, a ligament graft 80 can be introduced into the tibial
and femoral tunnels 52, 62. While various procedures known in the
art can be used to introduce the ligament graft 80 into the tibial
and femoral tunnels 52, 62, in one exemplary embodiment a suture 82
can be attached to a leading end of the ligament graft 80 and it
can be threaded through the tibial and femoral tunnels 52, 62
using, for example, a guide pin or other device. Tension can then
be applied to the suture to pull the ligament graft 80 up through
the tibial tunnel 52 and at least partially into the femoral tunnel
62. As shown in FIG. 3, the ligament graft 80 can be pulled to a
location that is spaced a distance apart from the end wall 62e of
the femoral tunnel, such that the ligament graft 80 stops short of
the transverse tunnel 66. Where the sleeve 70 extends into the
femoral tunnel 62, the sleeve 70 will prevent the ligament graft 80
from being fully advanced into contact with the end surface 62e of
the femoral tunnel 62.
[0043] As shown in FIG. 4, once the ligament graft 80 is positioned
within the femoral tunnel 62 the surgeon can inject an adhesive 98
into the femoral tunnel 62 to secure the ligament graft 80 therein.
While the adhesive 98 can be injected through any of the tunnels
using a variety of techniques, in the illustrated exemplary
embodiment the adhesive 98 is injected through the transverse
tunnel 66 using a syringe 90. In particular, the syringe 90 is
placed through the sleeve 70 in the transverse tunnel 66 and into
the femoral tunnel 62, and a plunger 92 on the syringe 90 is then
moved into a barrel 94 to eject the adhesive 98 from the barrel 94,
through the needle 96, and into the femoral tunnel 62. The amount
of adhesive 98 can vary, but in an exemplary embodiment, the
adhesive 98 fills a terminal end portion of the femoral tunnel 62
adjacent to the end surface 62e.
[0044] Once the terminal end portion of the femoral tunnel 62 is
filled with the adhesive 98, the suture 82 is further tensioned to
pull the ligament graft 80 into the terminal end portion such that
the ligament graft 80 abuts the end wall 62e of the femoral tunnel
62, as shown in FIG. 5. As a result, the ligament graft 80 is
brought into contact with the adhesive 98, which is spread in and
around the ligament graft 80. The adhesive 98 thus extends between
the end surface 62e and the ligament graft 80, and forms a cap that
surrounds the ligament graft 80, and optionally that extends into
portions of the ligament graft 80. In other embodiments, the
ligament graft 80 can be fully pulled into the femoral tunnel 62
and into contact with the end surface 62e, and then the adhesive 98
can be injected into the tunnel 62 until it completely surrounds
and encapsulates an end portion of the ligament graft 80.
[0045] Since the adhesive 98 can take time to cure, the first end
of the ligament graft 80 can be temporarily secured in the femoral
tunnel 62 using a fixation device. FIG. 6 illustrates one exemplary
embodiment of a fixation device in the form of a cross-pin 100 that
is used to secure the ligament graft 80 in the femoral tunnel 62.
As shown, the cross-pin 100 is in the form of an elongate member
that is inserted through the sleeve 70 in the transverse tunnel and
through a loop formed in the terminal end of the ligament graft 80.
The cross-pin 100 can also extend across the femoral tunnel 62 and
into a further portion of the transverse tunnel. In an exemplary
embodiment, the cross-pin 100 has a length that allows a portion of
the cross-pin 100 to remain outside of the sleeve 70 while the
remainder of the cross-pin 100 extends through the transverse
tunnel 66, through the graft 80, and completely across the femoral
tunnel 62. Once the ligament graft 80 is temporarily secured within
the femoral tunnel 62 using the cross-pin 100, the sleeve 70 can be
removed leaving the cross-pin 100 in place, as shown in FIG. 7. The
second end of the ligament graft 80 can also be tensioned and
secured within the tibial tunnel 52 using the same anchoring
technique, or using other anchoring techniques known in the art.
When the adhesive 98 is finally cured, the cross-pin 100 can be
removed leaving the ligament graft fixed within the femoral tunnel
62, as shown in FIG. 8.
[0046] A person skilled in the art will appreciate that the
cross-pin 100 can have a variety of configurations, and that
various other fixation devices known in the art can be used. For
example, while an elongate rod is shown, in other embodiments the
fixation device can be in the form of a screw or other anchoring
element. The fixation device can also be formed from a variety of
materials, but in certain exemplary embodiments it is preferably
formed from or coated with a material that prevents adhesion to the
adhesive. For example, the fixation device can be formed from or
coated with a fluoropolymer plastic resin, such as Teflon.RTM.. A
person skilled in the art will appreciate that a variety of other
materials can be used to prevent adhesive between the cross-pin and
the adhesive. The sleeve 70 can also optionally be formed from or
coated with a protective material that prevents adhesive to the
adhesive.
[0047] The materials used to form the adhesive can also vary, and
virtually any bone glue or cement known in the art can be used.
Since a cross-pin is temporarily used to maintain the ligament
graft within the femoral tunnel while the adhesive dries, the
drying time for the adhesive can significantly vary and the surgeon
has more freedom to select a desired adhesive. The adhesive can
also be bioabsorbable or non-absorbable. In certain exemplary
embodiments, the adhesive preferably has a viscosity that allows it
to be injected into the femoral tunnel without the adhesive
dripping, but that allows it to spread around the ligament graft as
the graft is pulled fully into the femoral tunnel. By way of
non-limiting example, exemplary adhesives include bone glues, such
as biocompatible bone glues including 2-octyl cyanoacrylate and the
like and equivalent thereof, bone cements, such as conventional
biocompatible bone cements including polymethylmethacrylate and the
like, as well as dental implant cements such as Premiere Dental
Implant Cements.
[0048] As previously indicated, the ligament graft can also have a
variety of configurations, and it can be directly affixed within
the bone tunnel, or an anchoring element can be used to affix the
ligament graft within the bone tunnel. FIGS. 9A-13 illustrates
various exemplary embodiments of ligaments grafts. In the
embodiments shown in FIGS. 9A-11C, each ligament graft is in the
form of a bone-to-bone graft that is mated to an anchoring element
having surface features that facilitate adhesion thereof within a
bone tunnel. In the embodiments shown in FIGS. 12A-12D, each
ligament graft is also in the form of a bone-to-bone graft,
however, rather than using an anchoring element, the bone graft is
modified to include surface features to facilitate adhesive thereof
within a bone tunnel. FIG. 13 illustrates yet another embodiment of
a ligament graft in the form of a soft tissue graft that is
attached to an anchoring element having surface features adapted to
facilitate adhesive thereof within a bone tunnel. A person skilled
in the art will appreciate that the ligament graft can have a
variety of other configurations, and that any combination of these
features or other features known in the art can be used. Moreover,
the various ligament grafts can be implanted using the techniques
previously described herein, or they can be implanted using various
other techniques known in the art.
[0049] As indicated above, in the embodiment shown in FIGS. 9A-9C,
an anchoring element 110 can be used to affix a bone-to-bone graft
120 within a bone tunnel. While the anchoring element 110 can have
a variety of configurations, in one exemplary embodiment it
preferably includes a first portion 112 that is adapted to be
adhesively mated to a bone tunnel, and a second portion 114 that
extends from the first portion 112 and that is adapted to mate to a
bone graft 122 of a bone-to-bone graft 120.
[0050] The first portion 112 can have a variety of configurations,
and various techniques can be used to facilitate adhesion between
the first portion 112 and a bone tunnel. In the illustrated
embodiment, the first portion 112 is in the form of a post having
an eyelet formed on a terminal end thereof. The eyelet includes an
opening 113 formed therein for receiving a suture which can be used
to pull the anchor 110 and ligament graft 120 attached thereto into
a bone tunnel. The eyelet, as well as the post, can also facilitate
adhesion of the first portion 112 to a bone tunnel, as an adhesive
will surround the post and extend into the eyelet, as shown in FIG.
9C. A person skilled in the art will appreciate that the first
portion can have a variety of other shapes, and it can include a
variety of other features formed thereon, such as grooves, bores,
protrusions, etc.
[0051] The second portion 114 of the anchor 110 can also have a
variety of configurations, and various techniques can be used to
mate the second portion 114 to a bone graft 122. As shown in FIGS.
9A-9C, the second portion 114 includes threads 114a formed thereon
for allowing the second portion 114 to be threaded into the bone
graft 120, as shown in FIG. 9B. Other mating techniques, including
adhesives, can be used to mate the second portion 114 to the bone
graft 122.
[0052] FIG. 10 illustrates another embodiment of an anchor 130 that
is adapted to mate to a bone graft, and that is adapted to be
affixed within a bone tunnel using an adhesive. The anchor 130 is
similar to the anchor 110 shown in FIG. 9A as it includes a first
portion 132 having a post and an eyelet, and a second portion 134
adapted to mate to a bone graft. In this embodiment, however, the
second portion 134 includes annular cut-out regions 116 formed
along a length thereof for receiving an adhesive. The adhesive can
be injected into and around the cut-out regions 116 and the second
portion 134 can be inserted into a bore drilled in a bone graft to
adhere the second portion 134 to the bone graft.
[0053] FIGS. 11A-11C illustrate yet another embodiment of an anchor
140 adapted to mate to a bone graft 152 of a bone-to-bone ligament
graft 50, and to be adhered within a bone tunnel. Similar to the
embodiments shown in FIGS. 9A-10, the anchor 140 includes a first
portion 142 having a post and an eyelet formed thereon, and a
second portion 144 that is adapted to mate to a bone graft. In this
embodiment, the second portion 144 includes opposed arms 145a, 145b
that are adapted to receive a bone graft 152 therebetween. While
the arms 145a, 145b can optionally be adhesively mated to the bone
graft 152, the arms 145a, 145b can also or alternatively be sutured
to the bone graft 152. Thus, the opposed arms 145a, 145b can each
include one or more thru-bores formed therein. FIGS. 11A-11C
illustrate two thru-bores 144a, 144b formed in each arm 145a, 145b.
Two corresponding thru-bores 152a, 152b can also be drilled through
the bone graft 152 to allow suture 146a, 146b to extend through the
bone graft 152 to attach the bone graft 152 to the arms 145a, 145b,
as shown in FIG. 11C. A person skilled in the art will appreciate
that various other techniques can be used to mate the bone graft
152 to the arms 145a, 145b, and that the arms 145a, 145b can have a
variety of other configurations. For example, the arms 145a, 145b
can threadably engage the bone graft 152.
[0054] In use, the anchoring elements 110, 130, 140 of FIGS. 9A-11C
can be implanted within a bone tunnel using various methods known
in the art. In an exemplary embodiment, however, the anchors 110,
130, 140 are affixed within a bone tunnel using the exemplary
methods previously described herein. In particular, after the
anchoring element 110, 130, 140 is attached to a bone graft, the
anchoring element 110, 130, 140 can be pulled through the tibial
tunnel and at least partially into the femoral tunnel. This can be
achieved using various techniques, for example, by tensioning a
suture that is attached to the eyelet of the anchor. An adhesive,
e.g., adhesive 98 as shown in FIG. 9C, can then be introduced into
the femoral tunnel, preferably via the transverse tunnel, to fill a
terminal end portion of the femoral tunnel. The anchor 110, 130,
140 can be further pulled into the femoral tunnel, causing the
adhesive to spread around the first portion of the anchor 110, 130,
140. Alternatively, the anchor 110, 130, 140 can be fully pulled up
into the femoral tunnel prior to introducing the adhesive. While
not necessary, a cross-pin can optionally be inserted through the
hole in the eyelet to maintain the anchor 110, 130, 140, and thus
the ligament graft, within the femoral tunnel until the adhesive
cures. Where a cross-pin is not used, a fast drying adhesive is
preferably used to allow the other end of the ligament to be
anchored in the tibial tunnel without having to wait an extended
period of time for the adhesive to cure.
[0055] In other embodiments, as previously discussed, the bone
graft itself can be modified to be adhesively affixed within a bone
tunnel. FIGS. 12A-12D illustrate various exemplary embodiments of
such bone grafts. In general, each bone graft, which includes a
ligament attached thereto, is modified to include surface features
formed thereon for receiving an adhesive therein. Such a
configuration allows the adhesive to completely surround and extend
into the bone graft, thereby providing a secure connection between
the bone graft and the bone tunnel. The shape, quantity, size, and
configuration of the surface features can vary. FIG. 12A
illustrates one embodiment of a bone graft 160 having a
cross-shaped groove 162 formed in a terminal end thereof. The
grooves can also extend along at least a portion of the sidewall of
the bone graft 160, as shown. In the embodiment shown in FIG. 12B,
the bone graft 170 includes annular cut-out portions 172 formed
therearound and spaced apart from one another along at least a
portion of a length of the bone graft 170. FIG. 12C illustrates yet
another embodiment of a bone graft 180 having thru-bores 182
extending therethrough for receiving the adhesive therein. In yet
another embodiment, shown in FIG. 12D, the bone graft 190 is
modified to include a reduced diameter region 192 such that the
bone graft includes a small post formed thereon. In each of the
embodiments, the cut-out portions can be formed using instruments
and techniques known in the art. In use, the cut-out portions allow
the adhesive to extend therein and surround the bone graft, thereby
mating the bone graft to the bone tunnel. The bone grafts can be
implanted using techniques previously described, or using other
techniques known in the art.
[0056] FIG. 13 illustrates another embodiment of a ligament graft.
In this embodiment, the ligament graft is in the form of a soft
tissue graft 210 that does not include a bone graft. The soft
tissue graft is mated directly to an anchor 200. The configuration
of the anchor 200 can vary, and various techniques can be used to
mate the soft tissue graft 210 to the anchor 200. In the
illustrated embodiment, the anchor 200 generally includes a first
portion 202 that is adapted to adhesively mate to a bone tunnel,
and a second portion 204 that is adapted to mate to the soft tissue
graft 210. The configuration of the first portion 202 can vary, but
it preferably includes features that facilitate mating thereof to a
bone tunnel. Any of the features previously described can be used
herein, including annular cut-out portions, as shown. In this
embodiment, the cut-out portions define flanges 206 which can help
maintain the anchor 200 within the bone tunnel, at least
temporarily until an adhesive is disposed therearound and cured to
lock the anchor 200 in place. The second portion 204 of the anchor
can also vary, and it can have virtually any shape and size that
facilitates attachment of a soft tissue graft 210 thereto. As shown
in FIG. 13, the second portion 204 includes an eyelet 207 formed
thereon for receiving the soft tissue graft 210. The second portion
204 also includes a wedge-shaped body 208 extending distally
therefrom. The wedge-shaped body 208 can help prevent back-out of
the anchor 200 once the anchor is inserted in a bone tunnel. In
particular, when tension is applied to the soft tissue graft 210,
the soft tissue graft 210 will cause the anchor 200 to pivot. As a
result, the wedge-shaped body 208 will extend into and engage the
wall of the bone tunnel, thereby preventing movement of the anchor
200 within the bone tunnel. A person skilled in the art will
appreciate that the anchor 200 can have a variety of other
configurations, and that it does not need to include any features
to facilitate back-out or to maintain the anchor 200 in a fixed
position, as an adhesive can be used to lock the anchor 200 within
the bone tunnel. In use, the anchor 200 can be implanted using
techniques previously described, or using other techniques known in
the art.
[0057] One of ordinary skill in the art will appreciate further
features and advantages of the invention based on the
above-described embodiments. Accordingly, the invention is not to
be limited by what has been particularly shown and described,
except as indicated by the appended claims. All publications and
references cited herein are expressly incorporated herein by
reference in their entirety.
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